The U.S. Environmental Protection Agency (EPA) on Dec. 14, 2012 announced it had adopted a national ambient air quality standard for annual fine particle pollution (particulate matter pollution 2.5 micrometers in diameter or PM 2.5) of 12 micrograms per cubic meter of air. On Thurs., Dec. 20, 2012, almost one week later, California’s San Joaquin Valley Air Pollution Control District (SJVAPCD) for the eight-county Valley followed suit and approved a 20-micrograms-per-cubic-meter-of-air fine-particle-pollution standard.
As I understand it, the EPA standard is “projected” to be met in all but seven of America’s more than 3,000 counties by the 2020 target date. The seven counties projected to not meet the federal standard are all located in California, three of those being in the San Joaquin Valley.
What I have learned since the posting earlier of three related articles, the EPA standard is an annual standard whereas the standard for the Valley is not; it is a daily health standard, which means anytime the 20 micrograms per cubic meter of air threshold for PM 2.5 is exceeded, the presumption is that burning wood in Valley fireplaces and woodstoves, will be prohibited. For residents who have no other way to heat their homes, via special permitting provisions, they will be permitted to use fireplaces or woodstoves on exceedance days, that is, according to how I interpret applicable language.
Besides this, the presumption is that as long as the 20 micrograms per cubic meter of air standard for PM 2.5 in the Valley is not exceeded, then fireplace and woodstove wood-burning is allowed. The problem with this as I see it, is that the air in Valley counties during wintertime weather patterns is frequently stagnant – or, at least, that’s the way it’s been in the past. So, assuming this still holds true, in areas of relative high population concentration, that is, with enough fireplaces and woodstoves going at the same time, when the air is stagnant, logic would have it that the likelihood is high the 20 micrograms per cubic meter of air standard will be violated in relative short order. Remember, there are currently roughly 4 million residents Valleywide.
Back to the target date issue, remembering for the EPA and SJVAPCD these are 2020 and 2019, respectively. As a less stringent PM 2.5 Valley standard compared to that of the EPA’s, and even though the federal agency’s standard is for annual ambient air quality of PM 2.5 versus a daily air standard in the Valley, it is difficult to see how the entire Valley will be able to meet the more stringent federal standard.
So the point is, if under such circumstances fireplace and woodstove activity is, in fact, what pushes PM 2.5 over the limit and the standard is therefore exceeded, at issue then will be recovery time, or in other words, the time it takes before air in the Valley returns to safe breathing levels to the point where once again, fireplace and woodstove wood burning is allowed to resume. All this has the appearance of being a paradox.
Could it be with this very thing in mind that there exists the distinct possibility that the outright banning of woodburning could be in effect all winter long in sizable Valley cities?
That residential and commercial wood burning may be stopped periodically is one thing. Meeting the national standard is quite another.